|MadSci Network: General Biology|
Although the sweating helps to maintain the body temperature, it is not the only reason for stimulation of sweating. For example, as soon as we enter sunny area, we may start sweating. On the contrary, sweating may not occur even when the body temperature is elevated as in case of fever. Also, even if we move into hotter environment, body temperature does not usually rise so easily. As a measure of precaution, the temperature is sensed by the skin and before the body temperature raises, necessary action is taken by the system. Sweating occurs when the change in temperature is abrupt. Sweating and evoporation of sweat are in equilibrium when the temperature is maintained at certain level. When the ambient temperature rises, the equilibrium is lost. Hence, the skin senses the rise in temperature and starts sweating to compensate for the rise in temperature. Another reason for sweating is humidity, which inhibits evoporation of the sweat leading to inefficient cooling of the body, which further leads to more sweating. The rise in body temperature may also occur due to strain or stress, which leads to increased metabolic activities. Locally, temperature can rise upto several degrees. However, sweating is stimulated in such situations not just by the temperature. Changes in hormonal activities during such stress conditions are responsible for stimulation of sweat glands. Hence, many things such as temperature, physical excercise, fear, strain, etc. work together for stimulating sweat glands. Under normal circumstances, abrupt change in temperature of the environment of about 3-5 deg C can stimulate sweating.
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